North Americans use more water than anyone else on the planet, and Okanagan region residents use twice as much as anyone else in Canada. Two professors in the Irving K. Barber School of Arts and Sciences at UBC’s Okanagan campus are looking for ways to reduce water use in the Okanagan Valley and other areas that experience similar demands for water.
Lawn or turf grass irrigation is the major drain on water supplies in the Okanagan, with 60 to 70 per cent of municipal water usage going toward residential lawn irrigation. Computer science associate professor Ramon Lawrence and his research team are developing sensor nodes that can predict and modify water distribution at the source of irrigation to use and waste less water during the irrigation process. Assistant biology professor Miranda Hart is proposing to combat the need for intense irrigation by diversifying the type of microbes found in the soil, which will minimize the need for irrigation.
Lawrence’s research team worked with the City of Kelowna last summer to study irrigation in a city park. One member of the team was an undergraduate funded by a research award through the Irving K. Barber Endowment. The park used traditional irrigation systems which watered according to predicted weather and precipitation patterns based on past events. The problem with this type of system according to Lawrence lies with the data.
“Traditional irrigation systems either require human programming or base their irrigation programs on weather observations,” says Lawrence. “The problem is that weather models are not exact, and there is no way for the system to self correct if the soil reaches saturation or if the weather does not occur as predicted. These systems do not easily adapt to changing conditions.”
The computer science team designed a system that adapted water use to actual conditions, aiming to lesson the amount of water wasted. The approach used three different nodes: a moisture sensor placed into the soil to collect information on the amount of water present; a sensing node responsible for scheduling and reporting soil moisture readings; and a controller node responsible for controlling and scheduling irrigation times and duration. All information was transmitted wirelessly, eliminating the need for costly wiring. The result of the adaptive watering program was 54 per cent less water usage with no noticeable effect on the appearance of the lawn.
Hart is proposing to further reduce water usage by adding microbes to the soil to reduce the amount of water needed to sustain grass and plants.
“There is a clear link between the diversity of belowground organisms and plant growth. By adding drought-resistant microbes to the soil, we hope to eliminate the need for watering while still allowing plants to be viable,” says Hart.
She says that often developers remove precious top soil during the building process, and if it is not replaced, the soil loses a lot of its ability to naturally retain water. She hopes to work with developers, the Okanagan Basin Water Board, xeriscaping associations and irrigation consultants to replace top soil and add microbes that will help create ideal growing conditions that are well-suited to the Okanagan climate and soils while minimizing water use.
Lawrence will likely work as a collaborator with Hart on her project, as both researchers are developing different tools toward the same goal – to reduce the amount of water used in the Okanagan for lawn maintenance. And both are excited about the possibility of how their research may also be applied in the future to broader uses such as agriculture or viticulture.
“We really want to raise awareness of little things that people can do that will pay off in a big way,” says Lawrence. “In the Okanagan, we don’t pay the true cost of water, so there is not a lot of financial incentive for people to save – but water is not an infinite resource, and there are many reasons other than monetary cost to limit the amount of water we use.”
Other researchers in the Irving K. Barber School of Arts and Sciences researching water conservation include:
Ph.D student Scott Fazackerley and associate professor of computer science Ramon Lawrence conducted research in a City of Kelowna park last summer using sensor nodes to collect information and schedule and report moisture levels and irrigation times.